Transmission links such as circuit traces, integrated circuit interconnect lines or pins, backplanes, wires or cables, antennas, air, or other transmission media may attenuate, delay, or otherwise change the characteristics of signals traveling through them. Signal attenuation may be frequency dependent; different frequency signal components can be attenuated by different amounts. In general, high-frequency signal components are attenuated more than lower frequency components. Phase delay or group delay caused by the transmission link may also be frequency dependent, causing different signal frequency components to arrive at the receiver or transceiver with different delays.
In a dielectric stack such as those commonly used in backplanes, transmission losses may be due to skin effect and dielectric losses. Skin effect losses may lead to intersymbol interference (ISI), which results in an increased bit error rate (BER). In some integrated circuit devices, active equalization circuits may be provided to improve signal transmission. An active equalization circuit may amplify higher frequency components more than lower frequency components to compensate for bandwidth loss. However, such an equalization technique is fairly complex as it needs to be accompanied by a decision feedback equalization (DFE) circuit, which typically uses feedback to reduce the ISI in a presently transmitted signal. In addition, the use of an active equalization circuit increases cost and power consumption for the receiver or transceiver.